Laws of Motion Part 1

Three masses M=100‌kg,m1=10‌kg and m2=20‌kg are arranged in a system as shown in figure. All the surfaces are frictionless and strings are inextensible and weightless. The pulleys are also weightless and frictionless. A force F is applied on the system so that the mass m2 moves upward with an acceleration of 2ms−2. The value of F is :
(. Take .g=10ms−2)